Method and apparatus of selectively tying the opening and closing of EVDO and PPP sessions

ABSTRACT

Method, and associated apparatus, for operating a hybrid access terminal operable in a CDMA 1x/EVDO hybrid communication session system. The hybrid access terminal is operable to communicate pursuant to an EVDO communication session and to a PPP communication session. The opening and closing of the communication sessions are independent of one another. Opening of one session does not require opening of another of the sessions. And, closing of one of the sessions does not require closing of the other of the sessions.

FIELD OF THE APPLICATION

The present application relates to mobile data devices and in particularto the establishment and taking down of EVDO and PPP sessions betweenthe mobile data device and the network.

BACKGROUND

A CDMA 1X/EVDO hybrid access terminal (mobile device) is a hybrid systemthat has evolved from the CDMA 2000 system. EVDO stands for EvolutionData Only or Data Optimized and, as suggested by this, is a data onlysystem. EVDO is also alternatively known as High Rate Packet Data(HRPD). One advantage of EVDO systems is that they allow a highertransfer rate for data. They are also useful to carriers to clear the 1Xsystem voice capacity by removing data traffic from the 1X system.

Once a hybrid access terminal has an EVDO session established,applications that use the EVDO air interface will need to open apoint-to-point protocol (PPP) session using Simple IP or Mobile IP.Current systems have two options for tying the PPP session with the EVDOsession. By default, the two are never tied. Alternatively, the two maybe always tied together.

The problem with this is that if EVDO and PPP sessions are always tiedtogether, situations exist where the EVDO session does not necessarilyneed to be closed when the PPP session is closed, or the PPP sessiondoes not necessarily need to be closed when the EVDO session is closed.If the two are not tied together, there are situations where it isdesirable to close both the EVDO session and the PPP session togetherand this may not happen if the two are not tied together.

BRIEF DESCRIPTION OF THE DRAWINGS

The present application will be better understood with reference to thedrawings in which:

FIG. 1 is flow chart showing the establishment of EVDO and PPP sessionsfor an always on hybrid access terminal;

FIG. 2 is a flow chart showing the establishment of a PPP session for analways on hybrid access terminal;

FIG. 3 is a flow chart showing the closing of an EVDO and/or a PPPsession for an always on hybrid access terminal;

FIG. 4 is a state machine diagram for an always on hybrid accessterminal;

FIG. 5 is a flow chart showing the opening and closing of EVDO and PPPsessions for a non-always on hybrid access terminal;

FIG. 6 is a network diagram showing an exemplary hybrid CDMA 1X/EVDOnetwork; and

FIG. 7 is an exemplary mobile device that can be used with the presentmethod.

DETAILED DESCRIPTION

The present method and apparatus overcome the deficiencies of the priorart by providing for the selective tying of an EVDO session opening orclosing with a PPP session opening or closing.

In hybrid access terminals that are always on devices, in other words,continuously have a data session active, the present method andapparatus provide that when an EVDO session is opened, the PPP sessionshould also be opened if it is not already open. Whenever either of theEVDO session or the PPP session is closed, the other does not have to beclosed unless the hybrid access terminal radio has been turned off. Aswill be appreciated by those skilled in the art, if the mobile deviceradio has been turned off then it is desirable to close both the EVDOand the PPP session in order to ensure that network resources are notunnecessarily used.

In the case of non always on devices, when the mobile device is poweredon, the EVDO session does not have to be opened unless an applicationthat uses packet data services is running. Once an application that usespacket data services is started, the EVDO network needs to be accessedand the EVDO and the PPP sessions are started. For non always ondevices, once the application is done with the data call, both the PPPand the EVDO sessions can be terminated to save network resources.

The present application therefore provides a method for selectivelytying an Evolution Data Only (EVDO) session and a point to pointprotocol (PPP) session in an always-on hybrid access terminal comprisingthe steps of when a radio on the hybrid access terminal is turned off,closing both the EVDO session and the PPP session; and when the radioremains on and one of the EVDO session and PPP session are closed,leaving the other of the EVDO session and PPP session open.

The present application further provides a method for selectively tyingan Evolution Data Only (EVDO) session and a point to point protocol(PPP) session in an always-on hybrid access terminal comprising thesteps of checking whether one of the EVDO session and the PPP sessionare open; if one of the EVDO session and PPP session are open, openingthe other of the EVDO Session and PPP session; and if neither of theEVDO session and PPP session are open, opening both the EVDO session andthe PPP session.

The present application still further provides an always-on hybridaccess terminal adapted for selectively tying an Evolution Data Only(EVDO) session and a point to point protocol (PPP) session, the hybridaccess terminal having a radio subsystem including a radio adapted tocommunicate with a network; a radio processor having a digital signalprocessor and adapted to interact with said radio subsystem; memory; auser interface; a processor adapted to run user applications andinteract with the memory, the radio and the user interface and adaptedto run applications, the hybrid access terminal characterized by havingmeans for: closing both the EVDO session and the PPP session when theradio on the hybrid access terminal is turned off; and leaving the otherof the EVDO session and PPP session open when the radio remains on andone of the EVDO session and PPP session are closed.

Reference is now made to FIG. 1. FIG. 1 illustrates a flow chart for analways on hybrid access terminal in which the initial precondition isthat the radio is off, and that there are no PPP or EVDO sessionsestablished in state 100.

The mobile device proceeds to step 110 in which the radio is turned on.Since the device is in an always on hybrid access terminal, it isdesirable that a data session be established and therefore the hybridaccess terminal proceeds to step 112 in which an EVDO session isestablished.

Once the EVDO session is established in step 112, the hybrid accessterminal proceeds to step 114 in which a PPP session is established.Once both the EVDO and the PPP sessions are established, the hybridaccess terminal proceeds to step 120 and ends the process.

As an alternative to FIG. 1, reference is now made to FIG. 2. FIG. 2shows an embodiment in which the initial state 200 has the radio on butthere is no EVDO session established. This could occur, for example, ata network boundary crossing in which the hybrid access terminal isinstructed to close its EVDO session and do a hand-off to a new EVDOnetwork. In this case, it may not be desirable to have a PPP sessiondropped since this will require negotiation with the new EVDO system toestablish a new PPP session, thus requiring more traffic on the networkand a higher battery usage on the hybrid access terminal. It istherefore desirable for an always on mobile device when crossing networkboundaries and in other situations in which the EVDO session is droppedbut the hybrid access terminal remains on to keep the PPP session open.

Referring to FIG. 2, the hybrid access terminal proceeds first to step210 in which it checks to see whether a PPP session is established. Aswill be appreciated, if the PPP session is established the hybrid accessterminal does not need to do anything else and will proceed to step 220in which the process is ended.

Conversely, if there is no PPP session established as determined in step210, the hybrid access terminal proceeds to step 212 in which itestablishes a PPP session before proceeding to step 220 in which theprocess is ended.

Referring to FIG. 3, FIG. 3 illustrates a flow chart for an always onhybrid access terminal in which the radio is on, an EVDO session isestablished and a PPP session is established as illustrated in state250.

The hybrid access terminal first proceeds to step 260 in which it checksto see whether the radio has been turned off. If the radio has beenturned off, the hybrid access terminal should drop its EVDO and its PPPsessions prior to the actual radio being turned off in order to savenetwork resources and to indicate to the hybrid access terminal that itno longer has an EVDO or a PPP session. Thus, from step 262 the hybridaccess terminal proceeds to step 262 in which the EVDO session is closedand next to step 264 in which the PPP session is closed. The hybridaccess terminal then proceeds to step 270 in which the process is ended.

Conversely, if the radio is not being turned off in step 260, the hybridaccess terminal proceeds to step 280 in which checks to see whether theEVDO session has closed. If the EVDO session has closed, the defaultbehaviour should be to leave the PPP session active and thus in step 282the hybrid access terminal leaves the PPP session active before endingthe process in step 270.

If in step 280 it is determined that the EVDO session has not closed,the hybrid access terminal proceeds to step 290 in which it checkswhether the PPP session has closed. Again, the default behaviour of thePPP session closes is to leave the EVDO session open and this is done instep 292. The hybrid access terminal then proceeds to step 270 and ends.

Conversely, from step 290 if the PPP session has not closed, then thehybrid access terminal can again proceed to step 270 and end theprocess.

As will be appreciated by those skilled in the art, instead of endingthe process at step 270, the hybrid access terminal could insteadcontinue to loop back to step 260 in which the check for the radio beingturned off is performed.

The above therefore provides the advantage that, by not tying the EVDOsession and the PPP session together when the radio is not turned off,network traffic is reduced and battery consumption on the device is alsoreduced. Specifically, since the hybrid access terminal will not teardown the EVDO session if the PPP session is brought down by either thedevice or the network, unnecessary traffic is avoided in order tore-establish the EVDO session subsequently.

Similarly, if the EVDO session is ended because of the hand-off betweena radio network controller (RNC) for one EVDO session and the secondEVDO session, the PPP session is not brought down and thus networktraffic is reduced and battery consumption on the hybrid access terminalis also reduced. The above would be equally applicable to situations inwhich the EVDO session is brought down for other reasons besidesboundary area transitions.

The above can also be seen with reference to the state diagram of FIG.4. The state diagram of FIG. 4 shows a hybrid access terminal is off instate 810. A second state 820 is when the device is on but the radio isnot on.

A third state is when the device is on and the radio is on in state 830.In both states 820 and 830, there is no PPP or EVDO session.

In state 840, the EVDO session is open but the PPP session mayor may notbe and in state 850, the PPP session and the EVDO sessions are bothopen.

Starting from the state where the hybrid access terminal is off, theonly option for the device is to turn the device on. This is done instep 812 and the hybrid access terminal proceeds to step 820 in whichthe device is on.

From state 820, the hybrid access terminal has two choices. Either thedevice is turned off in which case the hybrid access terminal proceedsback to state 810 or the radio is turned on in which case the hybridaccess terminal proceeds to state 830. This is done in either steps 822or 824 respectfully.

From state 830, the hybrid access terminal can turn the radio off. Inwhich case, the hybrid access terminal proceeds back to state 820through step 832.

Alternatively, the device can be turned off completely in which case thehybrid access terminal, in step 834, proceeds back to state 810.

Finally, if the radio has been turned on, the preferable thing for thehybrid access terminal to do is to proceed in step 836 to state 840 inwhich the EVDO session is opened.

Once the device is in state 840, it also has several options. A firstoption is if the device is turned off, in which case the hybrid accessterminal proceeds through step 842 back to state 810. Further, in step842 the EVDO session is closed. This ensures network resources are notwasted by having an unnecessary EVDO session open.

Alternatively, from state 840 the radio can be turned off but the devicecan remain on, in which case the hybrid access terminal proceeds back tostate 820 in step 844. Again, since the radio has been turned off, theEVDO session should be closed in step 844.

From state 840, the device can proceed to state 850 in step 846 in whichboth the PPP and the EVDO sessions are open.

From state 850, the hybrid access terminal can proceed to state 810 ifthe device is turned off in which case the EVDO session is closed andthe PPP session is closed in step 852.

Alternatively, from state 850, the radio can be turned off, in whichcase the EVDO session is closed and the PPP session is closed in state854 and the hybrid access terminal proceeds to state 820.

Reference is now made to FIG. 5. FIG. 5 illustrates a non-always ondevice in which the radio is off and there is no PPP or EVDO sessions instate 500. When the radio is turned on in step 510, the mobile devicenext checks to see whether or not there is an application that usespacket data service in step 512. If in step 512 it is determined thatthere is no application that has packet data service then step 512 keepsleaping on itself until an application that desires packet data serviceis open. At this time, the hybrid access terminal proceeds to step 514in which it opens an EVDO session and to step 516 in which it opens aPPP session.

Once the PPP session and the EVDO session are opened in steps 514 and516 the hybrid access terminal proceeds to step 520 in which it checkswhether the application is finished. If the application is finished, thehybrid access terminal proceeds to step 524 in which the PPP session andthe EVDO session are ended and to step 526 in which the process isended.

In step 520, if the application is not finished, the hybrid accessterminal continues to check until the application does finish beforeproceeding to step 524.

The above therefore provides for an always on device selectively tyingthe PPP session and the EVDO sessions together to optimize networktraffic and to minimize battery consumption on the hybrid accessterminal. Further, on an always on device, the two can be tied togethersince neither is required when an application with packet data servicesis not operating on the non-always on device.

Reference is now made to FIG. 6. FIG. 6 is a block diagram of anexemplary wireless data network in accordance with the presentapplication and with which the various embodiments of the method of theinstant application may cooperate. FIG. 6 shows a block diagram of awireless data device 310 and exemplary CDMA 1x network 320, an exemplaryEVDO network 330, a public switched telephone network (PSTN) 335, a datanetwork 340, wireless gateway 342 and e-mail server 344 with which theinstant techniques of this application may cooperate. The wireless datadevice 310 is preferably a two-way communication device having data andvoice communication capabilities.

CDMA network 320 is comprised of a base transceiver station (BTS) 322and a base station controller (BSC) 324. Base station controller 324communicates with a mobile switching centre 326 which as will beappreciated, is a circuit switched only component communicating withPSTN 335. Base station controller 324 further communicates with a packetdata serving node (PDSN) 328 which is a packet switched only component.PDSN 328 further communicates with IP network 340.

EVDO network 330 contains an EVDO sector 332, which communicates withaccess node (AN) 334. Since the EVDO network 330 is a data only network,access node 334 communicates only with PDSN 328 and not with any circuitswitch components.

An authentication, authorization and accounting node 336 is associatedwith AN 334, and a similar node 329 is associated with PDSN 328.

Operationally, hybrid access terminal 310 communicates wirelessly withCDMA network 320 using BTS 322 and BSC 324 to gain access to the CDMA 1xnetwork. As indicated above, the CDMA 1x network is given priority andthe establishment of the CDMA network occurs prior to any EVDO networkconnection being established.

Hybrid access terminal 310 sends and receives both data and voiceservices through CDMA network 320 until an EVDO network connection withestablished. Base station controller 324 communicates with circuitswitch services provided by MSC 326 such as voice and short messageservice (SMS) via PSTN 335.

Prior to an EVDO connection being established, hybrid access terminal310 further communicates wirelessly with BTS 322 and BSC 324 to gainaccess to packet data services provided by PDSN 328, such as e-mail,wireless application protocol (WAP) and other data services via datanetwork 340. Such services are provided through wireless gateway 342 andservers such as e-mail server 344.

Once a network connection is established with CDMA 1x network 320 andthe hybrid access terminal enters CDMA 1x idle state, wireless device310 establishes a connection with EVDO network 330. This is done throughEVDO sector 332 and AN 334. In this way, hybrid access terminal 310gains access to packet data services provided by PDSN 328 using EVDOnetwork 330. Subsequent to the establishment of an EVDO networkconnection with hybrid access terminal 310, CDMA network 320 is used toprovide circuit switched services such as voice and SMS while EVDOnetwork 330 is used to provide packet data services such as e-mail andWAP.

As will be appreciated by those skilled in the art, wireless device 310can include voice communication means such as a headpiece 352 or a usercan communicate directly into the wireless device 310.

A further advantage of the present system is that due to high transferrates associated with EVDO networks, wireless device 310 can be used asa wireless modem and be connected through various means such as a USB orother serial port, or by short range wireless communications with acomputer 354. Computer 354 can then gain access to data network 340through EVDO network 330 using hybrid access terminal 310 as the modem.

Reference is now made to FIG. 7. FIG. 7 is a block diagram illustratinga hybrid access terminal apt to be used with preferred embodiments ofthe apparatus and method of the present application. Hybrid accessterminal 400 is preferably a two-way wireless communication devicehaving at least voice and data communication capabilities. Hybrid accessterminal 400 preferably has the capability to communicate with othercomputer systems on the Internet. Depending on the exact functionalityprovided, the wireless device may be referred to as a data messagingdevice, a two-way pager, a wireless e-mail device, a cellular telephonewith data messaging capabilities, a wireless Internet appliance, or adata communication device, as examples.

Where hybrid access terminal 400 is enabled for two-way communication,it will incorporate a communication subsystem 411, including both areceiver 412 and a transmitter 414, as well as associated componentssuch as one or more, preferably embedded or internal, antenna elements416 and 418, local oscillators (LOs) 413, and a processing module suchas a digital signal processor (DSP) 420. As will be apparent to thoseskilled in the field of communications, the particular design of thecommunication subsystem 411 will be dependent upon the communicationnetwork in which the device is intended to operate. For example, hybridaccess terminal 400 may include a communication subsystem 411 designedto operate within the CDMA 1x/EVDO hybrid system.

Network access requirements will also vary depending upon the type ofnetwork 419. In some CDMA networks network access is associated with asubscriber or user of hybrid access terminal 400. A CDMA hybrid accessterminal may require a removable user identity module (RUIM) or asubscriber identity module (SIM) card in order to operate on a CDMAnetwork. The SIM/RUIM interface 444 is normally similar to a card-slotinto which a SIM/RUIM card can be inserted and ejected like a disketteor PCMCIA card. The SIM/RUIM card can have approximately 64K of memoryand hold many key configuration 451, and other information 453 such asidentification, and subscriber related information.

When required network registration or activation procedures have beencompleted, hybrid access terminal 400 may send and receive communicationsignals over the network 419. As illustrated in FIG. 7, network 419 canconsist of multiple base stations communicating with the hybrid accessterminal. For example, in a CDMA 1x EVDO system, a CDMA base station andan EVDO base station communicate with the hybrid access terminal and thehybrid access terminal is connected to both simultaneously. The EVDO andCDMA 1x base stations use different paging slots to communicate with thehybrid access terminal.

Signals received by antenna 416 through communication network 419 areinput to receiver 412, which may perform such common receiver functionsas signal amplification, frequency down conversion, filtering, channelselection and the like, and in the example system shown in FIG. 7,analog to digital (A/D) conversion. A/D conversion of a received signalallows more complex communication functions such as demodulation anddecoding to be performed in the DSP 420. In a similar manner, signals tobe transmitted are processed, including modulation and encoding forexample, by DSP 420 and input to transmitter 414 for digital to analogconversion, frequency up conversion, filtering, amplification andtransmission over the communication network 419 via antenna 418. DSP 420not only processes communication signals, but also provides for receiverand transmitter control. For example, the gains applied to communicationsignals in receiver 412 and transmitter 414 may be adaptively controlledthrough automatic gain control algorithms implemented in DSP 420.

Hybrid access terminal 400 preferably includes a microprocessor 438,which controls the overall operation of the device. Communicationfunctions, including at least data and voice communications, areperformed through communication subsystem 411. Microprocessor 438 alsointeracts with further device subsystems such as the display 422, flashmemory 424, random access memory (RAM) 426, auxiliary input/output (I/O)subsystems 428, serial port 430, a keyboard or keypad (or multiplekeyboards or keypads) 432, speaker 434, microphone 436, othercommunication subsystem 440 such as a short-range communicationssubsystem and any other device subsystems generally designated as 442.Serial port 430 could include a USB port or other port known to those inthe art.

Some of the subsystems shown in FIG. 7 perform communication-relatedfunctions, whereas other subsystems may provide “resident” or on-devicefunctions. Notably, some subsystems, such as keyboard 432 and display422, for example, may be used for both communication-related functions,such as entering a text message for transmission over a communicationnetwork, and device-resident functions such as a calculator or tasklist.

Operating system software used by the microprocessor 438 is preferablystored in a persistent store such as flash memory 424, which may insteadbe a read-only memory (ROM) or similar storage element (not shown).Those skilled in the art will appreciate that the operating system,specific device applications, or parts thereof, may be temporarilyloaded into a volatile memory such as RAM 426. Received communicationsignals may also be stored in RAM 426.

As shown, flash memory 424 can be segregated into different areas forboth computer programs 458 and program data storage 450, 452, 454 and456. These different storage types indicate that each program canallocate a portion of flash memory 424 for their own data storagerequirements. Microprocessor 438, in addition to its operating systemfunctions, preferably enables execution of software applications on thehybrid access terminal. These functions include executing the solutionspresented above. A predetermined set of applications that control basicoperations, including at least data and voice communication applicationsfor example, will normally be installed on hybrid access terminal 400during manufacturing. A preferred software application may be a personalinformation manager (PIM) application having the ability to organize andmanage data items relating to the user of the hybrid access terminalsuch as, but not limited to, e-mail, calendar events, voice mails,appointments, and task items. Naturally, one or more memory stores wouldbe available on the hybrid access terminal to facilitate storage of PIMdata items. Such PIM application would preferably have the ability tosend and receive data items, via the wireless network 419. In apreferred embodiment, the PIM data items are seamlessly integrated,synchronized and updated, via the wireless network 419, with the hybridaccess terminal user's corresponding data items stored or associatedwith a host computer system. Further applications may also be loadedonto the hybrid access terminal 400 through the network 419, anauxiliary I/O subsystem 428, serial port 430, short-range communicationssubsystem 440 or any other suitable subsystem 442, and installed by auser in the RAM 426 or preferably a non-volatile store (not shown) forexecution by the microprocessor 438. Such flexibility in applicationinstallation increases the functionality of the device and may provideenhanced on-device functions, communication-related functions, or both.For example, secure communication applications may enable electroniccommerce functions and other such financial transactions to be performedusing the hybrid access terminal 400.

In a data communication mode, a received signal such as a text messageor web page download will be processed by the communication subsystem411 and input to the microprocessor 438, which preferably furtherprocesses the received signal for output to the display 422, oralternatively to an auxiliary I/O device 428. A user of hybrid accessterminal 400 may also compose data items such as email messages forexample, using the keyboard 432, which is preferably a completealphanumeric keyboard or telephone-type keypad, in conjunction with thedisplay 422 and possibly an auxiliary I/O device 428. Such composeditems may then be transmitted over a communication network through thecommunication subsystem 411.

For voice communications, overall operation of hybrid access terminal400 is similar, except that received signals would preferably be outputto a speaker 434 and signals for transmission would be generated by amicrophone 436. Alternative voice or audio I/O subsystems, such as avoice message recording subsystem, may also be implemented on hybridaccess terminal 400. Although voice or audio signal output is preferablyaccomplished primarily through the speaker 434, display 422 may also beused to provide an indication of the identity of a calling party, theduration of a voice call, or other voice call related information forexample.

Serial port 430 in FIG. 7, would normally be implemented in a personaldigital assistant (PDA)-type hybrid access terminal for whichsynchronization with a user's desktop computer (not shown) may bedesirable, but is an optional device component. Such a port 430 wouldenable a user to set preferences through an external device or softwareapplication and would extend the capabilities of hybrid access terminal400 by providing for information or software downloads to hybrid accessterminal 400 other than through a wireless communication network. Thealternate download path may for example be used to load an encryptionkey onto the device through a direct and thus reliable and trustedconnection to thereby enable secure device communication. As will beappreciated by those skilled in the art, serial port 430 can further beused to connect the hybrid access terminal to a computer to act as amodem. A modem unit 460 interacts with a driver 462 in a computer 464 toallow data transfer through the hybrid access terminal. With EVDOnetworks, a high rate of data transfer can be achieved using the hybridaccess terminal 400 as the modem. Depending on the interface provided bydriver 462, unit 460 could be an IP routing module. Further, driver 462could provide either a modem interface or alternatively an IP interfaceto computer 464. As will be appreciated by those skilled in the art, thecombination of driver 462 and unit 460 must provide a communicationinterface for computer 430 to be enabled for communications originatedand/or terminated at computer 430.

Other communications subsystems 440, such as a short-rangecommunications subsystem, is a further optional component which mayprovide for communication between hybrid access terminal 400 anddifferent systems or devices, which need not necessarily be similardevices. For example, the subsystem 440 may include an infrared deviceand associated circuits and components or a Bluetooth™ communicationmodule to provide for communication with similarly enabled systems anddevices.

Advantageously, communications originating and/or terminating atcomputer 464 benefit from the techniques of this application as module460 preferably uses the techniques taught herein in a manner that istransparent to computer 464.

The embodiments described herein are examples of structures, systems ormethods having elements corresponding to elements of the techniques ofthis application. This written description may enable those skilled inthe art to make and use embodiments having alternative elements thatlikewise correspond to the elements of the techniques of thisapplication. The intended scope of the techniques of this applicationthus includes other structures, systems or methods that do not differfrom the techniques of this application as described herein, and furtherincludes other structures, systems or methods with insubstantialdifferences from the techniques of this application as described herein.

1. A method for selectively tying an Evolution Data Only (EVDO) sessionand a point to point protocol (PPP) session in an always-on hybridaccess terminal comprising the steps of: a. when a radio on the hybridaccess terminal is turned off, closing both the EVDO session and the PPPsession; and b. when the radio remains on and one of the EVDO sessionand PPP session are closed, leaving the other of the EVDO session andPPP session open.
 2. The method of claim 1, further comprising the stepof: a. if one of the EVDO session and PPP session are left open in theleaving step, opening the other of the EVDO session and PPP session. 3.The method of claim 1, further comprising the steps of: a. waiting forthe radio to be turned on; and b. after the radio is turned on, openingthe EVDO session and the PPP session.
 4. The method of claim 1, whereinthe leaving step leaves the PPP session open at a network boundarycrossing where the EVDO session is closed.
 5. The method of claim 1,wherein the leaving step leaves the EVDO session open if the PPP sessionis brought down by the network
 6. The method of claim 1, wherein theleaving step leaves the EVDO session open if the PPP session is broughtdown by the hybrid access terminal.
 7. A method for selectively tying anEvolution Data Only (EVDO) session and a point to point protocol (PPP)session in an always-on hybrid access terminal comprising the steps of:a. checking whether one of the EVDO session and the PPP session areopen; b. if one of the EVDO session and PPP session are open, openingthe other of the EVDO Session and PPP session; and c. if neither of theEVDO session and PPP session are open, opening both the EVDO session andthe PPP session.
 8. The method of claim 7, further comprising the stepsof: a. when a radio on the hybrid access terminal is turned off, closingboth the EVDO session and the PPP session; and b. when the radio remainson and one of the EVDO session and PPP session are closed, leaving theother of the EVDO session and PPP session open.
 9. The method of claim8, wherein the leaving step leaves the PPP session open at a networkboundary crossing where the EVDO session is closed.
 10. The method ofclaim 8, wherein the leaving step leaves the EVDO session open if thePPP session is brought down by the network
 11. The method of claim 8,wherein the leaving step leaves the EVDO session open if the PPP sessionis brought down by the hybrid access terminal.
 12. An always-on hybridaccess terminal adapted for selectively tying an Evolution Data Only(EVDO) session and a point to point protocol (PPP) session, the hybridaccess terminal having a radio subsystem including a radio adapted tocommunicate with a network; a radio processor having a digital signalprocessor and adapted to interact with said radio subsystem; memory; auser interface; a processor adapted to run user applications andinteract with the memory, the radio and the user interface and adaptedto run applications, the hybrid access terminal characterized by havingmeans for: a. closing both the EVDO session and the PPP session when theradio on the hybrid access terminal is turned off; and b. leaving theother of the EVDO session and PPP session open when the radio remains onand one of the EVDO session and PPP session are closed.
 13. The hybridaccess terminal of claim 12, further characterized by having means for:a. if one of the EVDO session and PPP session are left open by theleaving means, opening the other of the EVDO session and PPP session.14. The hybrid access terminal of claim 13, further characterized bymeans for: a. waiting for the radio to be turned on; and b. after theradio is turned on, opening the EVDO session and the PPP session. 15.The hybrid access terminal of claim 12, wherein the means for leaving isadapted to leave the PPP session open at a network boundary crossingwhere the EVDO session is closed.
 16. The hybrid access terminal ofclaim 12, wherein the means for leaving is adapted to leave the EVDOsession open if the PPP session is brought down by the network
 17. Thehybrid access terminal of claim 12, wherein the means for leaving isadapted to leave the EVDO session open if the PPP session is broughtdown by the hybrid access terminal.
 18. A method for operating a hybridaccess terminal that is operable to communicate in a first manner in afirst communication session and to communicate in a second communicationsession, said method comprising the operations of: a. selectably openingthe first communication session when the hybrid access terminal ispowered and capable of communicating; b. selectably opening the secondcommunication session when the hybrid access terminal is powered andcapable of communicating; c. selectably closing the first communicationsession, selection made irrespective of whether the second communicationsession is open; and d. selectably closing the second communicationsession, selection made irrespective of whether the first communicationsession is open.
 19. Apparatus for operating a hybrid access terminalthat is operable to communicate in a first manner in a firstcommunication session and to communicate in a second communicationsession, said apparatus comprising: a. a first session opener configuredselectably to open the first communication session when the hybridaccess terminal is powered and capable of communicating; b. a secondopener configured selectably to open the second communication sessionwhen the hybrid access terminal is powered and capable of communicating;c. a first session closer configured selectably to close the firstcommunication session, selection made irrespective of whether the secondcommunication session is open; and d. a second session closer configuredselectably to close the second communication session, selection madeirrespective of whether the first communication session is open.